St. Augustine Alligator Farm Zoological Park St Augustine Alligator Farm

still no

I think I know what you mean (that all captive individuals are a different species?). If so that is not correct.

O. tetraspis still exists. Any captive and wild animals belonging to tetraspis are still tetraspis. Individuals belonging to the split species are no longer tetraspis but that doesn't mean all captive/wild animals are not tetraspis.

St. Augustine has had, at least formerly, actual tetraspis. But I have no idea what their current animals are, or where they originated.

 

The precise situation is as follows; the type specimen for tetraspis was always identified as coming from a specific location in West Africa, and as such all individuals from this location have been classified thus. Recently, several populations have been identified as meriting species-status in their own right, some of which lack a scientific name as yet - however, in the process it was discovered that the source of the type specimen had been misidentified - it actually came from the Ogooué Basin in Central Africa. As such, none of the captive individuals previously classified as tetraspis belong to this taxon - this includes the "actual tetraspis" individuals at St Augustine to which you refer. The population in West Africa which was previously identified as tetraspis is yet to receive a scientific name.

In the meantime, a tiny handful of true tetraspis have been located in European collections; until the mix-up with the type locality was discovered, it was these which had been believed to require a new scientific name it is possible St Augustine has some of these, but if so they aren't the ones they previously identified as such.

 

The Ogooué Basin in Gabon has always been the type locality for tetraspis. So all Gabonese specimens, including the St. Augustine one which grouped with known Gabon-caught animals, were true tetraspis. Where are you getting the "wrong locality" from?

 

I was just repeating the current captive situation as it has been explained to me in discussion; as Thylo's reply would imply, he has obviously heard the same story

 

ok, well without wanting to sound too harsh I would say that whoever is giving you information is simply wrong - perhaps they have misinterpreted or just not understood the many scientific papers available on dwarf crocodile genetics - and you should have checked the facts for yourself.

The Ogooué Basin in Gabon is still the type locality - always has been - it can be checked all the way back to the original source; any suggestion that this is a "new discovery" or whatever is simply incorrect. Animals from Gabon and the surrounding area are still tetraspis; animals from the Congo Basin are osborni as has generally been the case, whether full species or subspecies or back to full species again; and then there are the [one, two, or more] as-yet-unnamed split species.

 

okay, I think I have found where the confusion may lie.

The original description of O. tetraspis was by Edward Drinker Cope in 1860 using a skin collected by Paul du Chaillu from the "Ogobai River" in Gabon [now Ogooué River] and a skull of unknown provenance obtained from the Pennsylvania University's museum. Thus the type locality is the Ogooué River and the type specimen is the skin from there. That's straight forward.

However the London Natural History Museum has a juvenile specimen collected in Old Calabar, Nigeria, which they have labelled in their collection catalogue as the type specimen of O. tetraspis tetraspis. Clearly this cannot be the case because the type specimen (of species and therefore also nominate subspecies) is the one collected by du Chaillu in Gabon. I'm not sure if Cope's type specimens still exist, so it is possible the London specimen was designated as a neotype, although this seems very unlikely given that it is a juvenile. It may also just be a simple mistake in their record system. In any case, that specimen does not negate the original type specimen and locality if the species was split - the Ogooué River group would still be tetraspis because that was the original type.

(Old Calabar is almost on the border with Nigeria and Cameroon, so by some divisions would still fall within tetraspis - it would depend on where the boundaries of the splits are in the end).

 

The other possibility is that both Thylo and myself got the wrong end of the stick regarding at what stage the taxonomic confusion arose; given the end situation it is possible the import/imports responsible for the West African Dwarf Crocodile population in captivity were misidentified as coming from the type locality when they did not, and that when this was explained to us we thought the error was with the type locality rather than the import

This would explain why, when work on the split started, all the individuals in Europe previously believed to be nominate turned out to belong to the undescribed taxa/taxon. It is only in the last year or so that further genetic testing has thrown up true nominate within the wider "no ssp known" population at collections such as Leipzig and Dudley.

 

I'm not sure I follow that reasoning (especially given that you would have both had to have independently misunderstood what you were told, which seems unlikely).

However, with regards to what you say, the major DNA study to determine what was captive in Europe involved museum and live (wild) specimens of known origin in combination with the living captive animals. That is how they determined where the individual zoo animals originated (by comparison with the known-origin samples), and therefore which species they belonged to, and how they determined which were hybrids. The results showed the complete opposite of what you say above - the bulk of the pure zoo animals were from the true tetraspis group, relatively few (only 12, out of 75 zoo specimens) were from the western group, only one was osborni, and then there was a little cluster of four animals which didn't fit with any of the three previous groups.

That study was the main one published in 2012 (here if you want to read it for yourself: https://www.researchgate.net/public...ocodylidae_and_consequences_for_European_zoos) and there has obviously been further testing of individuals since then, but the later tests certainly don't contradict the 2012 study that tetraspis is the commonest dwarf crocodile in European zoos, and that study itself contradicts your suggestion that "all the individuals in Europe previously believed to be nominate turned out to belong to the undescribed taxa/taxon" - it simply isn't true.

 

Given the fact that subsequent testing has suggested many of the individuals in the 2012 study (which I was already aware of) are indeed hybrids, I wouldn't be so sure about that; moreover, in terms of specific individuals mentioned in that study whose current taxonomic status I am familiar with, the Bristol and Plzen "tetraspis" are certainly now believed to be West African - that said, given one of the Bristol individuals grouped close to a Gabon wildcaught in the 2012 study, something odd is going on.

In any case, I'm not the zoochatter who is best informed on the cutting edge of Osteolaemus taxonomy; for that, you will have to speak to ophidia or zoogiraffe. Better yet, get to the UK and have a chat with Shaun Foggett of Crocodiles of the World. This book is also worth a read, although it only deals with the matter in passing.

 

mm, that's just going back to "what someone has told you" though - which given the previous conversation I wouldn't put any faith in personally. I'd rather see some actual published material about further results before I could comment on it.

 

I think jayjds2 was saying that the dwarf crocodile taxonomic situation is a mess, rather than the discussion about said situation However, I echo Thylo's interest in what you make of the taxonomic situation yourself!